scholarly journals Flexural Performance of FRP-Reinforced Geopolymer Concrete Beam

2020 ◽  
Vol 4 (4) ◽  
pp. 187
Author(s):  
Janeshka Goonewardena ◽  
Kazem Ghabraie ◽  
Mahbube Subhani

Fibre-reinforced polymer (FRP) rebar and geopolymer concrete (GPC) are relatively new construction materials that are now been increasingly used in the construction sectors. Both materials exhibit superior structural and durability properties that also make them a sustainable alternative solution. Due to the absence of any design standard for an FRP-reinforced GPC beam, it is important to validate the efficacy of available standards and literature related to other materials, e.g., FRP-reinforced conventional concrete or GPC alone. Four theories/design standards are considered for this comparison—ACI440.1R-15, CAN/CSA S806-12, parabolic stress block theory, and equivalent rectangular stress block theory for GPC under compression. The accuracy of these four approaches is also examined by studying the flexural performance of both the glass FRP (GFRP) and carbon FRP (CFRP). The FRP-reinforced beams are designed against the actual load they will be subjected to in a real-world scenario. It is concluded that parabolic stress block theory over-estimates the capacity, whereas CSA S806-12 yields the most accurate and conservative results. In addition, the flexural performance of the FRP-reinforced beams is evaluated in terms of ultimate, cracking, and service moment capacity, along with serviceable, ultimate, and residual deflection.

2021 ◽  

Concrete is the most versatile, durable and reliable material and is the most used building material. It requires large amounts of Portland cement which has environmental problems associated with its production. Hence, an alternative concrete – geopolymer concrete is needed. The general aim of this book is to make significant contributions in understanding and deciphering the mechanisms of the realization of the alkali-activated fly ash-based geopolymer concrete and, at the same time, to present the main characteristics of the materials, components, as well as the influence that they have on the performance of the mechanical properties of the concrete. The book deals with in-depth research of the potential recovery of fly ash and using it as a raw material for the development of new construction materials, offering sustainable solutions to the construction industry.


2015 ◽  
Vol 764-765 ◽  
pp. 1090-1094
Author(s):  
Tippabhotla D. Gunneswara Rao ◽  
P. Alfrite ◽  
G. Mallikarjuna Rao ◽  
Mudimby Andal

Geopolymer concrete (GPC) is a new construction material in which cement is totally replaced by calcined source materials fly ash and GGBS. Geopolymer utilization reduces or eliminates the use of cement whose production produces a lot of carbon dioxide. Usually fly ash as a source material for the geopolymer. The behavior of GPC has to be studied in detail to check its suitability in construction industry. In the present study, the fracture behavior of geopolymer concrete is investigated and compared. Three-point bending test on notched prisms with a/d (notch depth/beam depth) ratios 0.1, 0.15, 0.2 are considered. The values of Critical load, fracture toughness, fracture energy and ductility are presented. The test results of total of 27prisms, 6cubes, 18 cylinders with M30 grade geopolymer concrete and conventional concrete (OPC) of same grade are presented in this paper. The test results indicated that the characteristic length of GPC is about 25% more than that of conventional concrete.


2020 ◽  
Vol 184 ◽  
pp. 01101
Author(s):  
T. Srinivas ◽  
P. Bhavana ◽  
N. V. Ramana Rao

In recent days, the continuous running down of the ozone coat and global warming problem has greater than before, it is necessary to get the consciousness of the construction industries in using new recyclable construction materials. To suit this, geopolymer concrete has begun to boost massive concern from the research scholars and construction practitioners, because of its beneficial in utilizing byproduct materials to replace cement and diminishing ozone depleting substance release all through its generation. It is also having superior mechanical and durability properties compared to conventional concrete. On the other hand river sand is becoming scare day by day and costlier. So the manufactured sand turns out to be alternative material for river sand. In spite of its benefits, the use of geopolymer concrete in realistic is significantly narrow, this is primarily due to the deficiency in the studies in terms of structural elements, design and application. This paper objective is to identify the research gaps in this area and develop future research investigations in the materials and structural elements performance of geopolymer concrete. Many researchers from their analysis on flexural behavior of beams concluded that geopolymer concrete could replace conventional concrete.


2020 ◽  
Vol 38 (5A) ◽  
pp. 669-680
Author(s):  
Ghazwan K. Mohammed ◽  
Kaiss F. Sarsam ◽  
Ikbal N. Gorgis

The study deals with the effect of using Slurry infiltrated fiber concrete (SIFCON) with the reinforced concrete beams to explore its enhancement to the flexural capacity. The experimental work consists of the casting of six beams, two beams were fully cast by conventional concrete (CC) and SIFCON, as references. While the remaining was made by contributing a layer of SIFCON diverse in-depth and position, towards complete the overall depths of the built-up beam with conventional concrete CC. Also, an investigation was done through the control specimens testing about the mechanical properties of SIFCON. The results showed a stiffer behavior with a significant increase in load-carrying capacity when SIFCON used in tension zones. Otherwise high ductility and energy dissipation appeared when SIFCON placed in compression zones with a slight increment in ultimate load. The high volumetric ratio of steel fibers enabled SIFCON to magnificent tensile properties.


Author(s):  
Lakshmi Thangasamy ◽  
◽  
Gunasekaran Kandasamy ◽  

Many researches on double skin sandwich having top and bottom steel plates and in between concrete core called as steel-concrete-steel (SCS) were carried out by them on this SCS type using with different materials. Yet, use of coconut shell concrete (CSC) as a core material on this SCS form construction and their results are very limited. Study investigated to use j-hook shear studs under flexure in the concept of steel-concrete-steel (SCS) in which the core concrete was CSC. To compare the results of CSC, the conventional concrete (CC) was also considered. To study the effect of quarry dust (QD) in its place of river sand (RS) was also taken. Hence four different mixes two without QD and two with QD both in CC and CSC was considered. The problem statement is to examine about partial and fully composite, moment capacity, deflection and ductility properties of CSC used SCS form of construction. Core concrete strength and the j-hook shear studs used are influences the moment carrying capacity of the SCS beams. Use of QD in its place of RS enhances the strength of concrete produced. Deflections predicted theoretically were compared with experimental results. The SCS beams showed good ductility behavior.


2021 ◽  
Vol 11 (15) ◽  
pp. 6740
Author(s):  
Rana Muhammad Waqas ◽  
Faheem Butt

Geopolymer concrete, also known as an earth-friendly concrete, has been under continuous study due to its environmental benefits and a sustainable alternative to conventional concrete construction. The supplies of many source materials, such as fly ash (FA) or slag (SG), to produce geopolymer concrete (GPC) may be limited; however, quarry rock dust (QRD) wastes (limestone, dolomite, or silica powders) formed by crushing rocks appear virtually endless. Although significant experimental research has been carried out on GPC, with a major focus on the mix design development, rheological, durability, and mechanical properties of the GPC mixes; still the information available on the structural behavior of GPC is rather limited. This has implications in extending GPC application from a laboratory-based technology to an at-site product. This study investigates the structural behavior of quarry-rock-dust-incorporated fiber-reinforced GPC columns under concentric and eccentric loading. In this study, a total of 20 columns with 200 mm square cross-section and 1000 mm height were tested. The FA and SG were used as source materials to produce GPC mixtures. The QRD was incorporated as a partial replacement (20%) of SG. The conventional concrete (CC) columns were prepared as the reference specimens. The effect of incorporating quarry rock dust as a replacement of SG, steel fibers, and loading conditions (concentric and eccentric loading) on the structural behavior of GPC columns were studied. The test results revealed that quarry rock dust is an adequate material that can be used as a source material in GPC to manufacture structural concrete members with satisfactory performance. The general performance of the GPC columns incorporating QRD (20%) is observed to be similar to that of GPC columns (without QRD) and CC columns. The addition of steel fibers considerably improves the loading capacity, ductility, and axial load–displacement behavior of the tested columns. The load capacities of fiber-reinforced GPC columns were about 5–7% greater in comparison to the CC columns. The spalling of concrete cover at failure was detected in all plain GPC columns, whereas the failure mode of all fiber-reinforced GPC columns is characterized with surface cracking leading to disintegration of concrete cover.


2019 ◽  
Vol 28 (1) ◽  
pp. 81-88
Author(s):  
Miguel A. González-Montijo ◽  
Hildélix Soto-Toro ◽  
Cristian Rivera-Pérez ◽  
Silvia Esteves-Klomsingh ◽  
Oscar Marcelo Suárez

AbstractHistorically known for being one of the major pollutants in the world, the construction industry, always in constant advancement and development, is currently evolving towards more environmentally friendly technologies and methods. Scientists and engineers seek to develop and implement green alternatives to conventional construction materials. One of these alternatives is to introduce an abundant, hard to recycle, material that could serve as a partial aggregate replacement in masonry bricks or even in a more conventional concrete mixture. The present work studied the use of 3 different types of repurposed plastics with different constitutions and particle size distribution. Accordingly, several brick and concrete mix designs were developed to determine the practicality of using these plastics as partial aggregate replacements. After establishing proper working material ratios for each brick and concrete mix, compression tests as well as tensile tests for the concrete mixes helped determine the structural capacity of both applications. Presented results proved that structural strength can indeed be reached in a masonry unit, using up to a 43% in volume of plastic. Furthermore, a workable structural strength for concrete can be achieved at fourteen days of curing, using up to a 50% aggregate replacement. A straightforward cost assessment for brick production was produced as well as various empirical observations and recommendations concerning the feasibility of each repurposed plastic type examined.


2021 ◽  
Vol 42 ◽  
pp. 102471
Author(s):  
Ertugrul Erdogmus ◽  
Maria Harja ◽  
Osman Gencel ◽  
Mucahit Sutcu ◽  
Ali Yaras

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